[PATCH 06/16] arm: parse modules from DT during early boot.

[Ian Campbell <ian.campbell@citrix.com>]

The bootloader should populate /chosen/nr-modules with the number of
modules and then for each module 0..nr-modules-1 it should populate
/chosen/moduleN-{start,end} with the physical address of the module.

The hypervisor allows for 2 modules (kernel and initrd). Currently we
don't do anything with them.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
---
 xen/common/device_tree.c      |   57 +++++++++++++++++++++++++++++++++++++++++
 xen/include/xen/device_tree.h |    7 +++++
 2 files changed, 64 insertions(+), 0 deletions(-)

diff --git a/xen/common/device_tree.c b/xen/common/device_tree.c
index 3d1f0f4..226e3f3 100644
--- a/xen/common/device_tree.c
+++ b/xen/common/device_tree.c
@@ -229,6 +229,61 @@ static void __init process_memory_node(const void *fdt, int node,
     }
 }
 
+static void __init process_chosen_node(const void *fdt, int node,
+                                       const char *name,
+                                       u32 address_cells, u32 size_cells)
+{
+    const struct fdt_property *prop;
+    const u32 *cell;
+    paddr_t size;
+    int i, nr_modules;
+
+    prop = fdt_get_property(fdt, node, "nr-modules", NULL);
+    if ( !prop )
+    {
+        early_info.modules.nr_mods = 0;
+        return;
+    }
+
+    cell = (const u32 *)prop->data;
+    get_val(&cell, 1, (u64*)&nr_modules);
+
+    if ( nr_modules > NR_MODULES )
+    {
+        early_panic("too many modules %d > %d\n", nr_modules, NR_MODULES);
+    }
+
+    for ( i = 0; i < nr_modules; i++ )
+    {
+        struct membank *mod = &early_info.modules.module[i];
+        /* longest prop name is "start", single digit numbers of modules */
+        char propname[strlen("moduleX-start") + 1];
+
+        BUILD_BUG_ON(NR_MODULES > 9);
+
+        snprintf(propname, sizeof(propname), "module%d-start", i+1);
+        prop = fdt_get_property(fdt, node, propname, NULL);
+        if ( !prop )
+            early_panic("no start for module %d\n", i);
+
+        cell = (const u32 *)prop->data;
+        device_tree_get_reg(&cell, address_cells, size_cells,
+                            &mod->start, &size);
+
+        snprintf(propname, sizeof(propname), "module%d-end", i+1);
+        prop = fdt_get_property(fdt, node, propname, NULL);
+        if ( !prop )
+            early_panic("no end for module %d\n", i);
+
+        cell = (const u32 *)prop->data;
+        device_tree_get_reg(&cell, address_cells, size_cells,
+                            &mod->size, &size);
+        mod->size -= mod->start;
+    }
+
+    early_info.modules.nr_mods = nr_modules;
+}
+
 static int __init early_scan_node(const void *fdt,
                                   int node, const char *name, int depth,
                                   u32 address_cells, u32 size_cells,
@@ -236,6 +291,8 @@ static int __init early_scan_node(const void *fdt,
 {
     if ( device_tree_node_matches(fdt, node, "memory") )
         process_memory_node(fdt, node, name, address_cells, size_cells);
+    else if ( device_tree_node_matches(fdt, node, "chosen") )
+        process_chosen_node(fdt, node, name, address_cells, size_cells);
 
     return 0;
 }
diff --git a/xen/include/xen/device_tree.h b/xen/include/xen/device_tree.h
index 4d010c0..585fcc9 100644
--- a/xen/include/xen/device_tree.h
+++ b/xen/include/xen/device_tree.h
@@ -15,6 +15,7 @@
 #define DEVICE_TREE_MAX_DEPTH 16
 
 #define NR_MEM_BANKS 8
+#define NR_MODULES 2
 
 struct membank {
     paddr_t start;
@@ -26,8 +27,14 @@ struct dt_mem_info {
     struct membank bank[NR_MEM_BANKS];
 };
 
+struct dt_module_info {
+    int nr_mods;
+    struct membank module[NR_MODULES];
+};
+
 struct dt_early_info {
     struct dt_mem_info mem;
+    struct dt_module_info modules;
 };
 
 typedef int (*device_tree_node_func)(const void *fdt,
-- 
1.7.9.1